DDoS attacks to PBX

Question

I'm wondering if DDOS attacks to PBX or telecommunications systems is possibe real.

According to this links:

http://threatpost.com/en_us/blogs/firm-sees-more-ddos-attacks-aimed-telecom-systems-073112

http://news.softpedia.com/news/DDOS-Attacks-Against-Telecom-Systems-Cost-as-Little-as-20-16-Per-Day-284875.shtml

it is possible.

There are DDOs attacks to web servers, which mostly give them so much concurrent loads or connections that service get unavailable. Many government or non-profit organizations that suffered this kind of attacks, eventually could choose to shutdown their web server and that's it, waiting for these attacks to end.

For a DDOs attacks to PBX, I imagine that it would result in telephones getting busy or ringing all the time unstoppably. This kind of attack could really damage any kind organization.

Is it possible to do that or are we just in the beginnings?

Answer 1

Of course it is possible. Any system that provides services can be attacked. Ones that rely on shared resources just make the attack easier.

You can DoS the public (circuit-switched) telephone network by simply picking up every receiver attached to a switch -- at some point you will have occupied every available circuit, and the next person to pick up the phone won't be able to get a line.
You can DoS an entire neighborhood of landline phones by using a capacitive coupler to put an AC RINGING signal onto the phone line trunk (though the large truck of gear you would need to do this over any real distance for a large number of phones would limit the practicality), or by simply cutting the phone cable -- the original Denial of Service attack.

You can DoS a cell system by pumping out large amounts of RF interference, cutting power to cell towers, etc.

You can DoS a Voice over IP system in ways similar to attacking a web server or other internet-connected device (resource exhaustion, bandwidth exhaustion, UDP port exhaustion, router poisoning, etc.)